This invention relates to signal generating devices and, more particularly, to a control stick assembly for generating electrical signals representative of the coordinates of control stick displacement.
Miniature control sticks have been used for a number of years to generate electrical input signals in radio control systems for model airplanes, cars, boats, etc. Such miniature control sticks have also been put to other uses requiring generation of coordinate electrical signals responsive to a manual input.
In the described control stick assembly, displacement of the control stick along two orthogonal axes is coupled to orthogonally disposed input shafts of two potentiometers. Until recently, the control stick has usually been coupled to the potentiometer input shafts by gimbals. Each gimbal has a slot that captures the control stick. As the control stick moves, the gimbals rotate responsive thereto and turn the potentiometer input shafts. The gimbals are not load bearing members--loads exerted on the control stick are transferred directly to the control panel.
German utility model No. GM-78 29 428 discloses a control stick assembly in which the control stick is coupled to the potentiometer input shafts by load bearing cranks, rather than gimbals; which results in a simplification of design and fewer parts. All the support for the control stick is provided by the cranks. The control stick is effectively cantilevered from the ends of the potentiometer input shafts, leading to mechanical instability of the control stick support. The control stick feels to the user as though it is floating, which is a disconcerting sensation.